Chromobacterium violaceum: Difference between revisions

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Background

Microbiology

Gram-negative oxidase-positive bacillus
- The violacein pigment is produced during aerobic growth at 22 ºC and can interfere with the oxidase test
Colonies are deep purple to black due to the presence of the violacein pigment and may have an almond-like odor
Found in water and soil, primarily tropics or subtropics

Epidemiology

Mostly tropical or subtropical areas, especially southeast Asia
Also in southeast US, most commonly Florida
CGD is a risk factor for opportunistic infection, as is G6PD deficiency

Clinical Manifestations

Causes wound infections following contaminated water exposure
Typically starts with a cellulitis
Always with systemic features, including fever (100%) and sepsis (82%)
Often bacteremia (60%) and can cause abscesses in visceral organs (51%), especially lung and liver
High mortality (53%)

Differential Diagnosis

Includes other causes of skin and soft tissue infection after water exposure
Common bugs: Staphylococcus aureus, Streptococcus pyogenes, other streptococci, Klebsiella, Pseudomonas aeruginosa, Escherichia coli, and polymicrobial infections
Uniquely marine bacteria: Aeromonas, Vibrio vulnificus, Shewanella, Edwardsiella, Chromobacterium
Others: Burkholderia pseudomallei, non-tuberculous mycobacteria, and some fungi

Management

Fluoroquinolones, chloramphenicol, tetracyline, TMP-SMX, imipenem, gentamicin
Maybe cefotaxime, ceftazidime, imipenem
Avoid first- and second-generation cephalosporins

@@ Line 1: / Line 1: @@
+==Background==
-= ''Chromobacterium violaceum'' =
+===Microbiology===
+*[[Stain::Gram-negative]] oxidase-[[Oxidase::positive]] [[Shape::bacillus]]
-== Microbiology ==
+**The violacein pigment is produced during aerobic growth at 22 ºC and can interfere with the oxidase test
+*Colonies are deep purple to black due to the presence of the violacein pigment and may have an almond-like odor
+*Found in water and soil, primarily tropics or subtropics
+===Epidemiology===
-* Gram-negative bacterium
-* Colonies are deep purple to black due to the presence of the violacein pigment
-* Found in water
+*Mostly tropical or subtropical areas, especially southeast Asia
-== Epidemiology ==
+*Also in southeast US, most commonly Florida
+*[[CGD]] is a risk factor for opportunistic infection, as is [[G6PD deficiency]]
+==Clinical Manifestations==
-* Mostly tropical or subtropical areas, especially southeast Asia
-* Also in southeast US, most commonly Florida
-* CGD is a risk factor for opportunistic infection, as is G6PD deficiency
+*Causes wound infections following contaminated water exposure
-== Clinical Presentation ==
+*Typically starts with a [[cellulitis]]
+*Always with systemic features, including [[Causes::fever]] (100%) and [[Causes::sepsis]] (82%)
+*Often [[Causes::bacteremia]] (60%) and can cause abscesses in visceral organs (51%), especially lung and liver
+*High mortality (53%)
+==Differential Diagnosis==
-* Causes wound infections following contaminated water exposure
-* Always with systemic features, including fever (100%) and sepsis (82%)
-* Often bacteremic (60%) and can involve visceral organs (51%), especially lung and liver
-* High mortality (53%)
+*Includes other causes of skin and soft tissue infection after water exposure
-== Differential Diagnosis for SSTI After Water Exposure ==
+*Common bugs: [[Staphylococcus aureus]], [[Streptococcus pyogenes]], other [[streptococci]], [[Klebsiella]], [[Pseudomonas aeruginosa]], [[Escherichia coli]], and polymicrobial infections
+*Uniquely marine bacteria: [[Aeromonas]], [[Vibrio vulnificus]], [[Shewanella]], [[Edwardsiella]], [[Chromobacterium]]
+*Others: [[Burkholderia pseudomallei]], [[non-tuberculous mycobacteria]], and some [[fungi]]
+==Management==
-* Common bugs: ''Staph'', ''Strep'', polymicrobial, ''Klebsiella'', ''Pseudomonas aeruginosa'', ''E. coli''
-* Uniquely marine bacteria: ''Aeromonas'', ''Vibrio'', ''Shewanella'', ''Edwardsiella'', ''Chromobacterium''
-* Others: ''Burkholderia pseudomallei'', NTMs, some fungal infections
+*[[Fluoroquinolones]], [[chloramphenicol]], [[tetracyline]], [[TMP-SMX]], [[imipenem]], [[gentamicin]]
-== Management ==
+*Maybe [[cefotaxime]], [[ceftazidime]], [[imipenem]]
+*Avoid first- and second-generation cephalosporins
+==Further Reading==
-* FQs, chloramphenicol, tetracyline, TMP-SMX, imipenem, gentamicin
+*[https://doi.org/10.1016/j.jcma.2011.08.013 ''Chromobacterium violaceum'' infection: a clinical review of an important but neglected infection]. ''J Chin Med Assoc''. 2011;74(10):435-41.
-== Further Reading ==
+[[Category:Gram-negative bacilli]]
-* [https://doi.org/10.1016/j.jcma.2011.08.013 ''Chromobacterium violaceum'' infection: a clinical review of an important but neglected infection]. ''J Chin Med Assoc''. 2011;74(10):435-41.
+{{DISPLAYTITLE:''Chromobacterium violaceum''}}